A semiconductor testing process is used to test the electrical characteristics and functionalities of packaged IC products after IC packaging processes so as to ensure the functional completeness of the IC products. Further, the testing process also includes categorizing the tested IC products according to their electrical performance. The testing results are used as the evaluation basis for grading the IC products. Finally, the testing process also includes checking the appearance of the IC products. An electrical testing of the IC products is mainly focused on a variety of electrical parameters of the IC products. The electrical testing ensures that the IC products are able to function properly.
The conventional two-point testing method, such as Kelvin testing, etc., often utilizes double parallel top-probes or double parallel gold-fingers. The top-probes and the gold-fingers have a few limitations.
First, the manufacturing accuracy is relatively low. With the continuous shrinking of the critical dimension of semiconductor devices, the size of the tested terminals and/or the distance between different tested terminals are also continuously shrunk. To match such size and distance shrinkage, the limitations of the distribution of the conventional double top-probes and the double gold-fingers become more prominent. Thus, the accuracy requirements has become more and more strict. Sometimes, it is even unable to use the distribution with double top-probes or double gold-fingers.
Second, the structural strength is relatively low. To achieve a two-point testing in the limited space on the tested terminal, the top-probes and the gold-fingers have to be thinner and thinner. Thus, the mechanical strength of the top-probes and the gold fingers is correspondingly lower and lower.
Third, the life span is relatively short. The conventional top-probes and gold-fingers are easily worn. Especially, when the accuracy requirements are relatively high and the mechanical strength is relatively low, the wear may be more severe; and the life span of the testing fixture is reduced.
Fourth, the testing accuracy is relatively low. To adapt to the requirements of the miniaturization of semiconductor devices, the resistance of the top-probes and gold-fingers with the smaller and smaller size is continuously increased. When the top-probes or gold-fingers are used to test a relatively large current, a relatively large voltage drop is generated. The relatively large voltage drop would affect the testing results. Further, it is easy for the parallel-distributed top-probes or gold-fingers to generate a distance difference. The distance difference would also affect the testing results. Further, to reduce the distance between two probes, the conventional double top-probes are usually distributed with inclining faces back-to-back. It is easy for the probes to spin out from the tested terminal because of the torque force of the spring in testing apparatus. Thus, the testing accuracy is affected. The disclosed device structures and methods are directed to solve one or more problems set forth above and other problems.